This type of wheel supporting system is disclosed in, for example, Patent Document 1.
In this wheel supporting system, as is shown in FIG. 22, a double row angular ball bearing 120 as a rolling bearing which includes an inner ring 121, an outer ring 130 and balls (rolling elements) 141, 142 is assembled to an outer circumferential surface of a hub shaft 113 of a wheel hub 110.
On the other hand, on an outer ring 160 of a constant velocity joint 150 to which an end portion of a drive shaft 151 is coupled, an outer ring shaft 163 is extended integrally from an end face 162 of an outer ring shaft 161 thereof.
In addition, internal splines 114 are formed on an inner circumferential surface of an inside hole in the hub shaft 113 of the wheel hub 110, and external splines 164 are formed on an outer circumferential surface of the outer ring shaft portion 163 in such a manner as to mesh with the internal splines 114.
In addition, the outer ring shaft portion 163 is fittingly inserted into the inside hole in the hub shaft 113 of the wheel hub 110 while the internal and external splines 114, 164 are being caused to mesh with each other, and by a fastening nut 166 being fastened on to a male thread portion 165 which is caused to project from a distal end of the outer ring shaft portion 163, the wheel hub 110 and the constant velocity joint are connected together in such a manner that torque can be transmitted therebetween.
Patent Document 1: JP-A-2002-114004